The skin forms the limiting layer between the organism and its environment. The most important object of the skin is to protect the interior of the body against exogenous influence. The skin comes into contact daily with foreign-to-body substances, in part hostile to a body, and specifically, hostile to the skin. Particularly frequent contact of the unprotected skin with these substances, which is often conditioned upon occupation (hairdressers, housewives, dentists), therefore leads sooner or later to more or less serious skin injuries. In order to avoid or at least to decrease the skin injuries, previously two principal types of measure have been introduced, indeed a protective skin cover as well as conserving skin care.
The protective skin cover involves treating the skin before contact with the foreign-to-the-skin substances in order to thereby extensively avoid direct contact between the skin surface and the harmful substances. The preparations which assure a protective skin cover work by chemical-physical activity, without invading into the physiology of the skin. Such preparations must particularly fulfill the following requirements: they should be impermeable and insoluble with regard to most exogenous substances; they should display a good skin compatibility; they should be easy to apply and also to remove again from the skin surface; they should not impair the grip of the hands and thereby their workability; and should display a certain maintenance duration. The disadvantage of the known preparations of this type is that they are not capable of optimally fulfilling all of these requirements. With the so-called conserving skin treatment, the skin is made less susceptible upon contact with the substances harmful to the skin. The skin cover substances are already contained in washing agents. One distinguishes their activities by various types of skin protection measures, and indeed such measures which act by means of absorption into the skin surface, refatting measures, acidifying measures and degelling measures. Here, too, the essential disadvantage of these skin protection meaures in that they are not effective in equal manner against all aggressions of the various environmental substances.